When the lens or lens nucleus is removed from the eye during cataract surgery, it is common to replace the lens with an intraocular lens implant. Intraocular lenses are optical implants for the replacement of the human lens in the visual correction of aphakia. Intraocular lens implants generally include a circular optical portion and one or more support structures extending outwardly from the optical portion, known as the haptics. The haptics support and fix the lens in position once the lens is inserted. Such intraocular lenses may be inserted either in the anterior chamber or posterior chamber of the eye following either intracapsular or extracapsular cataract extraction. However, the preferred location for the lens of the present invention is the capsular bag in the posterior chamber with the optic portion of the lens centered under the pupil. The preferred surgical technique is extracapsular cataract extraction.
Although the haptics are essential for supporting and positioning the lens once it is inserted in the eye, they make the lens more difficult to insert into the small and delicate eye chambers. The large and cumbersome haptics projecting from the optical portion are very difficult to maneuver. To eliminate this problem, surgeons in the past have tied the haptics together with a stitch of thread, pulling the haptics inwardly toward the lens body, as disclosed in U.S. Pat. No. 4,249,271. Thus, the lens is easier to insert due to its reduced span. However, the stitch may be easily broken during manipulation of the lens, resulting in an even greater chance of injury as the haptics snap outwardly. Moreover, it may be unnecessarily time consuming and difficult for the surgeon to properly stitch the haptics together. Additonally, it is necessary to insert a sharp surgical scalpel into the eye chamber after the lens is inserted to cut the stitch and release the haptic. This can be a dangerous and difficult procedure. In more conventional insertion techniques with a forcep, almost all manipulation of the lens takes place outside the eye chamber.
Other intraocular lenses, such as the Woods lens marketed by Copeland Intra Lenses, Inc., have used hooked haptics which hook to apertures in the optic portion of the lens. This also is unsatisfactory in that the hooked haptic can be easily displaced during lens insertion causing eye tissue trauma. Moreover, the hooked haptic has a relatively sharp, pointed end which can damage eye tissue.